radioulnarinivelissä

The radioulnar joints are a set of articulations between the radius and the ulna, two long bones in the forearm. There are three distinct radioulnar joints: the proximal radioulnar joint, the distal radioulnar joint, and the intermediate radioulnar joint which is essentially the interosseous membrane.

The proximal radioulnar joint is located at the elbow, where the head of the radius articulates with the radial notch of the ulna. This articulation is primarily a pivot joint, allowing for pronation and supination of the forearm. The annular ligament plays a crucial role in holding the head of the radius in place within this joint.

The distal radioulnar joint is located at the wrist, where the head of the ulna articulates with the ulnar notch of the radius. This is also a pivot joint, and it works in conjunction with the proximal radioulnar joint to facilitate the rotational movements of the forearm. The articular disc of the distal radioulnar joint separates the ulna from the carpal bones.

The interosseous membrane is a strong fibrous sheet that runs between the shafts of the radius and the ulna, effectively forming the intermediate radioulnar joint. It provides stability to the forearm and also serves as an attachment site for muscles. Together, these three radioulnar joints are essential for the complex movements of the hand and wrist, allowing for a wide range of supination and pronation.